By: Cristina Ellis
Summer has long been synonymous with visits to the seaside. All season long, people flock to the coast to soak up the sun and frolic in the crashing waves, but few know how these unique landforms come to be.
Beaches are narrow strips of sloping land along the edge of lakes, rivers, or oceans. They are covered by various materials, including sand, rocks, and even shells. Beaches are formed by erosion caused by the water that borders them. Over time, the water wears away at the land and nearby rocks, forming sand.
The changing tides deposit more sand and ocean sediment on the shore, creating the beaches we so enjoy. Constructive waves build up beaches the most because they have a strong swash (the thin sheet of water that washes up after a wave breaks) and a weak backwash. Commonly, sandier beaches are found where the water is shallow, as waves have less energy.
Waves and tides aren’t the only things that affect these coastal landforms; changing weather patterns due to seasonal changes also affect beaches. During winter, storm winds can pick up sand and carry it through the air. This action causes beaches to be eroded and can form sandbars. During the calmer summer months, waves retrieve sediment from the sandbars and carry it back to the beach. Because of this, beaches tend to be narrower and have steeper drop-offs in the winter, and tend to be wider and have a gentler slope in the summer.
Winds also create another unique feature of beaches: sand dunes. These dunes form when the wind blows sand into a sheltered area behind a large obstacle; over time, the sand accumulates into a small mound. Every dune has a windward side (the side on which the wind blows and pushes the sand upwards) and a slipface. Usually, the slipface is smoother than the textured windward side. These dunes have many benefits. In addition to providing a natural barrier against erosion, they also serve as a protective barrier from storm surges, saving coastal communities from flooding.
Beaches hold a special place in many people’s hearts as an enduring symbol of summer. This year, when you find yourself wandering down the shore, be sure to stop for a minute and appreciate the natural splendor around you. Beaches are the product of years of work by Mother Nature and are not to be taken for granted.
Sources:
https://education.nationalgeographic.org/resource/beach/
https://education.nationalgeographic.org/resource/dune/
Featured Image Source: Martide
The Fieldston Science Bulletin 
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